The sun has officially set on “Selling Sunset” star Emma Hernan’s on-again-off-again romance — ’cause TMZ’s learned it’s off again … and this time, the breakup came with a very dramatic exit!

Sources with direct knowledge tell TMZ the split went down after a blowout fight at Blake Davis‘ home in early February, where tensions boiled over and unresolved issues came spilling out … pushing Emma to cut their hangout short and hop on a jet to get out of there.

We’re told the argument was so explosive, Emma didn’t even stick around for a proper goodbye … and to make it official, she hit him with an IG unfollow, which eagle-eyed fans clocked Monday.

Sources close to Emma say she genuinely tried to make it work, but the relationship had grown increasingly toxic.

She’s not leaving any room for misinterpretation this time — Emma’s been telling friends the breakup is final, and she’s gone radio silent on Blake’s attempts to reach her via text.